This invention pertains to a furnace, which is adapted to contain molten zinc, molten aluminum, or other molten metal, and which thus is useful in die-casting facilities. The furnace may be a melting or holding furnace.
As exemplified in U.S. Pat. No. 3,996,412 and U.S. Pat. No. 4,027,862, it is known for a furnace of similar utility to comprise a vessel, which is adapted to contain such molten metal, and which is lined with a refractory material. The refractory material may be cast, compacted, or comprised of refractory bricks set in a suitable mortar. In any event, it is necessary for the furnace to be relined from time to time, and it is difficult, expensive, and time-consuming job to reline the furnace.
As exemplified in U.S. Pat. No. 4,208,043, it is known for a vessel for such molten metal to be constructed of rigid ceramic plates, which have complementary joints, which have felted ceramic inserts sealing the joints, and which are assembled with screw fasteners. The innermost plates, which contain such molten metal, cannot be removed readily. U.S. Pat. No. 4,222,337 and U.S. Pat. No. 4,222,338 exemplify prior art of related interest.
As exemplified in German Auslegeschrift No. 1,807,001, it is known for a crucible for molten metal to comprise an outer vessel and an inner vessel and for an intermediate layer of glass wool, mineral wool, or other fibrous material to be provided between the lateral walls of the outer and inner vessels.
As exemplified in U.S. Pat. No. 3,345,059, it is known for a crucible for molten metal to comprise an outer vessel, which has double insulative shells, and an inner vessel, which is positioned snugly within the inner shell of the outer vessel, for an "expansion" layer to be provided between the lateral walls of the inner and outer shells of the outer vessel, for an intermediate layer of granular material, which may be alumina powder, to be provided between the bottom walls of the inner and outer shells of the outer vessel, and for similar material to be packed between the outer vessel and a metal box, which encloses the outer vessel. It is disclosed that the "expansion" layer is "preferably aluminum-silicate fibers, refractory pebbles or crushable shapes."
As exemplified in U.S. Pat. No. 4,012,029, it is known for a tundish for molten metal to have an intermediate layer of particulate material between its permanent outer and expendable inner linings.
As exemplified in U.S. Pat. No. 3,898,366, it is known in a vessel for molten metal for electrical conductors to be imbedded in a refractory wall of the vessel, and for the conductors to close an electrical circuit so as to actuate an indicating means when the refractory wall has worn sufficiently to expose the conductors to the molten metal.